23 Oct 2026 15:48:27 UTC
Tornado before 6.3.3 HTTP Request Smuggling via Content-Length
cve-program · CVE-2023-54397 · Published
CVE-2023-54397
Tornado before 6.3.3 HTTP Request Smuggling via Content-Length
CVSS 4.0 9.0 CRITICALCVSS 3.1 7.5 HIGHCheck source for fixed versionsKEV status unknown
cve-program · CVE-2023-54397
PublishedTornado before 6.3.3 contains an HTTP request smuggling vulnerability due to improper parsing of Content-Length headers accepting non-standard characters. Attackers can send crafted HTTP requests with these characters to bypass proxy validation and smuggle requests when deployed behind certain proxies.
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